Advancements in communication technologies have permitted the development and deployment of many different types of communication systems that permit the effectuation of many different types of communication services. Communication systems are regularly utilized by many users to communicate therethrough pursuant to many varied communication services. Some communication services have become practical necessities of modern society. And, access to appropriate communication systems is a necessity for many.
As technological advancements continue, improved, and new, communication services shall likely become available. In general, the technological advancements provide for more efficient communications, at higher communication rates, or in manners that better provide for successful communications in spite of adverse communication conditions.
Technological advancements include advancements in digital communication techniques. Many modern communication systems utilize digital communication techniques to facilitate communication of data. Various communication advantages are provided through the use of digital communication techniques. Use of digital communication techniques, for example, permit redundancies to be removed from data prior to its communication, thereby permitting improved communication efficiencies. Improved communication efficiencies, in turn, permit data throughput rates of data communicated during operation of the communication system relative to a corresponding communication system that does not make use of digital communication techniques.
A radio communication system is an exemplary type of communication system. Advancements in communication technologies have been implemented in modern radio communication systems that have been developed and deployed. Many modern radio communication systems make use of digital communication techniques that, when implemented, form digital radio communication systems.
Data is communicated during operation of a radio communication system upon radio channels, defined upon a portion of the electromagnetic spectrum. Communication stations operable in a radio communication system operate variously to convert data that is to be communicated into a form capable of communication on the radio communication channel and to detect the data communicated thereon, thereby to permit the recovery of the informational content thereof.
Radio communication systems provide various advantages over their wireline counterparts. Because a wireline connection is not required to interconnect the communication stations of a radio communication system, communications are effectuable between communication stations between which wireline connections cannot easily be formed. And, because the wireline connection is not required to interconnect the communication stations, a radio communication system is amenable for implementation as a mobile communication system. In a mobile communication system, one or more of the communication stations between which data is communicated pursuant to effectuation of a communication service is provided mobility.
An exemplary type of radio communication system is a cellular communication system. A cellular communication system makes use of a plurality of fixed-site base transceiver stations that are deployed at spaced locations throughout an area that is to be encompassed by the communication system. Each base transceiver station defines a coverage area, referred to as a cell. Telephonic communication is effectuated through use of a mobile node that transceives data with a base transceiver station. Through the use of the plurality of base transceivers, positioned at the spaced locations, a base transceiver station is generally positioned in relatively close proximity to a mobile station positioned in an area encompassed by the communication system. Only relatively low-powered signals are required to be communicated between the mobile node and a base transceiver station to effectuate communications therebetween. The same channels are reusable at different base transceiver stations according to a cell reuse pattern.
Cellular communication systems are constructed to be operable in conformity with an operating specification promulgated by a standard-setting regulatory body. Successive generations of operating standards have been promulgated and corresponding successive generations of cellular communication systems have been deployed. A significant portion of the populated area of the world is encompassed by one or more generations of cellular communication systems.
The network infrastructures of more than one generation of cellular communication systems might, for instance, be installed over a common area and be concurrently operable to provide for radio communications with mobile stations operable in the respective communication systems. And, separate networks, operated by separate network operators, of the same generation, might also be installed over the common area, also to be operable concurrently.
A mobile node is authorized to communicate by way of a cellular communication system through purchase of a service subscription to communicate therethrough. Generally, pursuant to the service subscription, the mobile node is associated with a home network. The home network is typically the network that is installed to encompass an area in which the user of the mobile node is anticipated most regularly to be positioned. However, due to the inherent mobility of a mobile node, the user of the mobile node, carrying the mobile node, might roam beyond the coverage area of the home network of the mobile node. When roaming beyond the home network, the mobile node might instead be positioned at a location encompassed by another network, a visited network.
When the mobile node roams beyond its home network, the mobile node is selectably permitted to communicate by way of one or more of the visited networks, depending upon, among other things, whether the mobile node and the visited network operate pursuant to the same operating specification. Also, agreements between operators of the visited and home networks are further determinative of whether the mobile node is able to communicate by way of a particular visited network.
The mobile node might roam into an area encompassed by more than one network such that more than one network is available to a mobile node through which to communicate. A decision is made as to which of the available networks that the mobile node communicates. Conventional mechanisms are used in the decision-making process, typically including use of a defined set of preferred roaming partners. An operator of the home network of the mobile node maintains a list of preferred networks that are to be used through which to communicate when the mobile node roams beyond the home network. Historically, the preferred roaming lists are based upon capability of the visited networks having voice capability pursuant to circuit-switched connectivity.
Increasingly, however, cellular communication systems, and the mobile nodes operable therein, provide for packet communication services. Many new networks, constructed to be operable pursuant to new-generation operating specifications, provide packet connectivity permitting packet data services while, in contrast, some legacy networks provide only circuit-switched connectivity. When packet communication services are to be effectuated by a roaming mobile node, selection of the visited network through which to communicate based upon conventional criteria, i.e., based upon merely the capacity of a visited network to handle voice communications is inadequate to ensure that a packet data communication service shall acceptably be effectuated in that network.
Accordingly, an improved manner by which to select a network through which a roaming mobile node communicates is needed.
It is in light of this background information related to the communication packet-formatted data in a radio communication system that the significant improvements of the present invention have evolved.